1. Field of the Invention
The present invention relates to a car interior sheet manufactured by using a defective product (defective hygiene product), which is generated in the manufacturing process of hygiene products, and a hygiene product (waste hygiene product), which is wasted after use, among hygiene products such as tissues or diapers including wet-strength paper made of pulp including plastic or super absorbent polymer (SAP). In more particular, the present invention relates to a car interior sheet using a hygiene product, which is manufactured by attaching surface layers such as a nonwoven fabric to both surfaces of a base layer of the car interior sheet including 30 weight % to 50 weight % of a pulverized material, which is obtained by pulverizing a hygiene product, 5 weight % to 15 weight % of additives, and 30 weight % to 50 weight % of thermoplastic resin, and a manufacturing method thereof.
2. Description of the Related Art
In general, for example, a car interior material, that is, a car interior sheet may include a head liner, a door trim, a rear shelf, a sunroof cover, a package tray trim, a luggage cover, an engine cover, a trunk mat, a car mat, and a bonnet.
The car interior sheet includes a plurality of laminates in which surface and base layers are laminated. In detail, the base layer includes polypropylene (PP), polyethylene (PE), acrylonitrile butadiene styrene copolymer (ABS) resin, wood fiber, wood stock or resin felt. The surface layer includes a polyvinylchloride (PVC) film, polyethylene foam, or nonwoven paper. The car interior sheet is formed by attaching the surface layer to both surfaces of the base layer.
Most car interior sheets include foams. However, most foams employ petrochemicals, which are environment hazardous substances that cannot be recycled, as main source materials. The materials cannot be recycled and elate toxic materials by heat when the materials are combusted to contaminate soil or degrade water quality, thereby causing environmental pollution. In addition, the car interior sheet generates a large amount of toxic chemical ingredients, which cause harm to a human body, from a product in the manufacturing process to a complete product. Even if time elapses, the toxic chemical ingredients are not removed, so that health problems may be caused to a worker or a user.
Recently, in order to solve the problem, the car interior sheet has been manufactured by using natural materials such as wood flour, which is formed by pulverizing wood, or straw. However, when the natural materials are used, the natural materials have weak stiffness so that physical properties such as tensile strength or flexural rigidity may be degraded. In addition, when the car interior sheet is manufactured by introducing a large amount of natural materials in order to solve the problem, the thickness and the weight of the car interior sheet are increased, so that the fuel efficiency of a car is degraded. Accordingly, the work efficiency and the manufacturing cost may be increased.
In addition, the car interior sheet must have a fine appearance and represent superior performance in thermal insulation, sound insulation, sound absorption, cushioning, and formability in which a car can be easily molded according to the structural changes of the car resulting from the variation of the complex interior structure of the car and a car model. Accordingly, continuous studies and researches are required on a car interior sheet to overcome the above problems and represent superior performance.
As related arts, there are Korea Patent Registration Nos. 10-0607405, 10-1254496, 10-0437869, and 10-1069903.